Non-Aqueous Solution of Plant-Growth Regulator(s) and Polar and/or Semi-Polar Organic Solvent(s)

ABSTRACT

The present invention generally relates to non-aqueous solutions of plant growth regulator(s) and polar and/or semi-polar organic solvent(s), methods for making said non-aqueous solution, and methods for improving the growth and crop productivity of plants using said non-aqueous solution.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention generally relates to non-aqueous solutions ofplant growth regulator(s) and polar and/or semi-polar organicsolvent(s), methods for making said non-aqueous solution, and methodsfor improving the growth and crop productivity of plants using saidnon-aqueous solution.

2. Description of the Background

As provided in International Publication No. WO 2012068473, the contentsof which are expressly incorporated herein by reference, plant growthand development as well as productivity (e.g., crops, seeds, fruitsetc.) are known to be regulated by growth factors, mineral componentsand small molecules that signal for the expression of genes that enhancethe level of plant productivity, whether in quantity or quality.Traditional approaches for improving plant productivity have includedthe application of various minerals and nitrogen components as necessaryadditions or substrates to crop plant or other plant productivity.However, such approaches have tended to knowingly, or unknowingly,disregard the growth factors (e.g., phytohormones and/or other smallmolecules) required for enhanced productivity.

Traditionally, mineral fertilizers have been predominately applied togrowing crop plants. Difficulties arise, however, when external stressesimpede successful plant development, especially of grain or seed cropsand/or other crops. Physical stresses, such as those inflicted byenvironmental temperatures being either too low or too high, and inparticular high temperatures, are especially problematic. Moreover, thestate-of-the-art agronomic practice does not employ plant growthregulators to overcome a plant's difficulty, due to such stresses, inproducing sufficient amounts of nutrients, e.g., sugars, to preventautophagy (i.e., cannibalization of previously-formed plant cells bynewly-forming cells to compensate for a dearth of cell nutrients). It iswell known that mineral fertilizers provide eighteen minerals that arenecessary for crop growth and development. Signaling molecules, such asplant growth regulators or other molecules, are known to enhance cropproductivity through the expression of certain genes. Furthermore, muchresearch has been conducted into the use of plant growth regulators andtheir effects on plant growth and development.

An alternative, more natural approach, which is becoming ever moreappreciated, is based upon the theory that plants already have thenecessary genes/genetic code to produce greater quantities and/orqualities of various plant tissues as well as to thrive in the face ofcommon adversities, such as drought, disease, and insect infestations.But, to realize the full expression of this innate genetic material andthe plant's full potential, the plant must receive variousnaturally-occurring nutrients and/or phytohormones in specificconcentrations, at specific times during the plant's growth, and tospecific parts or tissues of the plant.

As provided in International Publication No. WO 2005/021715, thecontents of which are expressly incorporated herein by reference, planthormones have been known and studied for years. Plant hormones may beassigned to one of a few categories: auxins, cytokinins, gibberellins,abscisic acid, brassinosteroids, jasmonates, salicylic acids,polyamines, peptides, nitric oxides, strigolactones and ethylene.Ethylene has long been associated with fruit ripening and leafabscission. Abscisic acid causes the formation of winter buds, triggersseed dormancy, controls the opening and closing of stomata and inducesleaf senescence. Gibberellins, primarily gibberellic acid, are involvedin breaking dormancy in seeds and in the stimulation of cell elongationin stems. Gibberellins are also known to cause dwarf plants to elongateto normal size. Cytokinins, are produced primarily in the roots ofplants. Cytokinins stimulate growth of lateral buds lower on the stem,promote cell division and leaf expansion and retard plant aging.Cytokinins also enhance auxin levels by creating new growth frommeristematic tissues in which auxins are synthesized. Auxins, promoteboth cell division and cell elongation, and maintain apical dominance.Auxins also stimulate secondary growth in the vascular cambium, inducethe formation of adventitious roots and promote fruit growth.

The most common naturally occurring auxin is indole-3-acetic acid (IAA).However, synthetic auxins, including indole-3-butyric acid (IBA);naphthalene acetic acid (NAA); 2,4-dichlorophenoxy acetic acid (2,4-D);and 2,4,5-trichlorophenoxy acetic acid (2,4, 5-T or Agent Orange) areknown. While these are recognized as synthetic auxins, it should beacknowledged that IBA does naturally occur in plant tissues. Many ofthese synthetic auxins have been employed for decades as herbicides,producing accelerated and exaggerated plant growth followed by plantdeath. Agent Orange gained widespread recognition when it was usedextensively by the United States Army and Air Force in defoliationapplications during the Vietnam War. 2, 4-D finds continuing use in anumber of commercial herbicides sold for use in agriculture, right ofway, and turf and ornamental markets.

Agriculturally, active ingredients are often provided in the form ofconcentrates suitable for dilution with water. Many forms ofagricultural concentrates are known and these consist of the activeingredient and a carrier, which can include various components.Water-based concentrates are obtained by dissolving, emulsifying and/orsuspending agriculturally active technical materials in water. Due tothe relatively complex supply chain for crop protection agents, suchconcentrate formulations can be stored for long periods and may besubjected during storage and shipping to extreme temperature variations,high-shear and repetitive vibration patterns. Such supply chainconditions can increase the likelihood of formulation failure due to,for example, water mediated degradation and stability problems.

Accordingly, the efficient use of aqueous systems with certainagrochemicals and crop protection agents is restricted due to their poorchemical stability when exposed to water during storage. Typically,hydrolysis is the most common water-mediated degradation mechanism;however, agricultural concentrates with water-sensitive activeingredients are also subject to oxidation, dehalogenation, bondcleavage, Beckmann rearrangement and other forms of degradation onexposure to water.

In some cases it may be desirable to combine different agrochemicals toprovide a single formulation taking advantage of the additive propertiesof each separate agrochemical and optionally an adjuvant or combinationof adjuvants that provide optimum biological performance. For example,transportation and storage costs can be minimized by using a formulationin which the concentration of the active agrochemical(s) is as high asis practicable and in which any desired adjuvants are “built-in” to theformulation as opposed to being separately mixed inside the spray tank.The higher the concentration of the active agrochemical(s) however, thegreater is the probability that the stability of the formulation may bedisturbed, or that one or more components may phase separate.

Another challenge arises where a user of an agrochemical liquidconcentrate formulation dilutes the formulation in water (for example ina spray tank) to form a dilute aqueous spray composition. Suchagrochemical spray compositions are widely used, but their performancesometimes can be limited by the tendency for certain agrochemicals todegrade in a spray tank on exposure to water. For example, agrochemicalbreakdown can increase with increasing alkalinity and water temperature,and with the length of time the spray composition is left in the tank.

Considering the variety of conditions and special situations under whichagrochemical liquid concentrate formulation are stored, shipped and usedaround the world, there remains a need for concentrate formulations ofagrochemicals, including water sensitive agrochemicals that providestability benefits under at least some of those conditions andsituations. There is a further need for such formulations having highloading that are stable before being diluted with water under a widerange of field conditions.

US 20120045497 documents the stabilizing of liquid agrochemicalcompositions which comprise flowable, non-aqueous dispersionconcentrates comprising a continuous substantially water-miscible liquidphase, a dispersed water-immiscible liquid phase, and a colloidal solid.

Furthermore, it is known that gibberellins and abscisic acid cannot bedirectly applied to a crop and require a solvent system as a carrier forsuch applications. Since gibberellins are slowly hydrolyzed in aqueoussolutions, they cannot be stored long term in aqueous solutions.Commercial solutions are thus non-aqueous. Gibberellins are known to bedissolved in methanol. Methanol is both flammable and poisonous. TheDangerous Goods Regulations (DGR) therefore demand that all productswhich contain methanol, including gibberellin solutions, be marked asboth flammable and poisonous and handled accordingly which has led toincreased restrictions in some states and countries. Accordingly, US20030013610 proposes the use of a lipophilic solvent system. It has beenfound that the lack of solubility of gibberellins in lipophilic solventshas been overcome through the use of certain lipophilic solvent systems.This is of interest because they are not flammable like methanol. Suchsystems include a plant growth promoter composition comprising: (a) notin excess of 20% by weight of one or more gibberellins; and (b) anessentially non-aqueous solvent system comprising: (i) 30 to 99% byweight of one or more lipophilic solvents; (ii) at least an equivalentmolar amount to the gibberellin(s) of one or more lipophilic alkalinecoupling agents which enable the gibberellin(s) to form a lipophilicsolvent soluble complex; (iii) 1 to 50% by weight of one or moreemulsifiers which blend with the lipophilic solvent(s) to form ahomogeneous product and enable dispersion of the composition into waterfor application; and (iv) optionally, not in excess of 15% by weight ofone or more viscosity reducing co-solvents.

SUMMARY OF THE INVENTION

The present invention is directed to a non-aqueous solution of: 1) atleast one plant growth regulator and 2) at least one polar organicsolvent and/or at least one semi-polar organic solvent. The presentinvention further includes methods for making said non-aqueous solution,and methods for improving the growth and crop productivity of plantsusing said non-aqueous solution. A polar organic solvent is defined asthat which dissolves ionic and other polar solutes. Semi-polar organicsolvents induce a certain degree of polarity in non-polar molecules. Ameasurement of polarity may be determined by its dielectric constant.Semi-polar organic solvents and polar organic solvents defined in thisinvention are those organic solvents that have dielectric constantsgreater than 10 @ 20° C. For example, polar organic solvents mayinclude, but are not limited to alcohols, dialkyl ketones, alkylenecarbonates, alkyl esters, and aryl esters. For example, semi-polarorganic solvents may include, but are not limited to polyethyleneglycols of various molecular weights. The present invention includesmethods by which plant growth can be manipulated through the addition ofsaid non-aqueous solution by application to roots or aerial tissues.

The present invention is directed to methods for improving the growthand crop productivity of plants by introducing plant growth regulators,such as phytohormones, to the tissue of the plant using polar andsemi-polar organic solvent(s). In the methods of the present invention,a plant hormone in an amount effective to produce the desired effect,e.g., improved growth, improved fruit set, or improved plantarchitecture, is dissolved in polar and semi-polar organic solvent(s)and applied as an aqueous solution to the plant tissue.

The non-aqueous solution containing plant growth regulators has enhancedstability compared to aqueous composition by the use of the polar andsemi-polar organic solvent(s). This improved stability of thenon-aqueous solution preserves more biochemical activity compared to thetraditional aqueous compositions. This improves plant architecture byproducing a stockier, more compact plant characterized by increasedbranching, shorter stem internodes, prolific root development andthicker leaves with enhanced photosynthetic capacity and sugarproduction. This architectural change increases photosynthate storagecapacity; flowering points; fruit initiation, sizing and retention; andultimately yield.

DETAILED DESCRIPTION OF THE INVENTION

The non-aqueous solution of the present invention includes: 1) at leastone plant growth regulator, also referred to herein as PGR, and 2) atleast one polar organic solvent and/or at least one semi-polar organicsolvents. Herein are also disclosed methods for making said non-aqueoussolution and methods for improving the growth and crop productivity ofplants using said non-aqueous solution. The present invention includesmethods by which plant growth can be manipulated through the addition ofsaid non-aqueous solution by application to plant tissue.

As provided herein, it is understood that the term “non-aqueous” mayinclude small amounts of water, preferably less than 5 wt. %, preferablyless than 4 wt. %, preferably less than 3 wt. %, preferably less than 2wt. %, preferably less than 1 wt. %, and preferably less than 0.5 wt. %.However, it is preferred that water is not intentionally added to thepresent non-aqueous solution.

Plant Growth Regulators/Phytohormones

While the plant growth regulators (PGRs) provided in the non-aqueoussolution may be any effective plant hormones, the phytohormone istypically selected from ethylene, auxins, cytokinins, gibberellins,abscisic acid, brassinosteroids, jasmonates, salicylic acids, peptides,polyamines, nitric oxide, strigolactones, precursors, derivatives andmixtures thereof.

The auxin is preferably selected from the group consisting of thenatural auxins, synthetic auxins, auxin metabolites, auxin precursors,auxin derivatives and mixtures thereof. The preferred auxin is a naturalauxin, most preferably indole-3-acetic acid. The presently preferredsynthetic auxin is indole-3-butyric acid (IBA). Other exemplarysynthetic auxins which may be employed in the present invention includeindole 3-propionic acid, indole-3-butyric acid, phenylacetic acid,naphthalene acetic acid (NAA), 2,4-dichlorophenoxy acetic acid,4-chloroindole-3-acetic acid, 2,4,5-trichlorophenoxy acetic acid,2-methyl-4-chlorophenoxy acetic acid, 2,3,6-trichlorobenzoic acid,2,4,6-trichlorobenzoic acid, 4-amino-3,4,5-trichloropicolinic acid andmixtures thereof.

The cytokinin is preferably selected from one or more of the following:zeatin, various forms of zeatin, N6-benzyl adenine,N6-(delta-2-isopentyl) adenine, 1,3-diphenyl urea, thidiazuron, CPPU(forchlorfenuron), kinetin or other chemical formulations with cytokininactivity. The preferred cytokinin is kinetin.

The gibberellin is preferably selected from one or more of thefollowing: GAi, GA2, GA₃, GA4, GA5, GA6, GA7, GA₈, GA9, GA10, GA11,GA,2, GA,₃, GA,₄, GA,₅, GA₁₆, GA₁₇, GA,₈, GA₁₉, GA₂₀, GA₂i, GA₂₂, GA₂₃,GA₂₄, GA₂₅, GA₂₆, GA₂₇, GA₂₈, GA₂₉, GA₃₀, GA₃₁, GA₃₂, GA₃₃, GA₃₄, GA₃₅,GA₃₆, GA₃₇, GA₃₈, GA₃₉, GA₄₀, GA₄₁, GA₄₂, GA₄₃, GA₄₄, GA₄₅, GA₄₅, GA₄₇,GA48, GA₄₉, GAso, GA₅₁, GA₅₂, GA₅₃, GA₅₄, GA₅₅, GA₅₆, GA₅₇, GA₅₈, GA₅₉,GA₆₀, GA₆₁, GA₆₂, GA₆₃, GA₆₄, GA₆5, GA₆6, GA₆₇, GA₆₈, GA₆₉, GA₇₀, GA71,GA₇₂, GA₇₃, GA₇₄, GA₇₅, GA₇₆, GA₇₇, GA₇₈, GA₇₉, GA₈₀, GA₈i, GA₈₂, GA₈₃,GA₈, GA₈₅, GA₈₆, GA₈₇, GA₈₈, GA₈₉, GA₉o, GA₉i, GA₉₂, GA₉₃, GA₉₄, GA₉₅,GA₉₆, GA₉₇, GA₉₈, GA{circumflex over ( )}, GA100, GA101, GA₎₀₂, GAio₃,GA104, GA105, GA106, GAio₇, GAios, GAi₀₉, GAno, GAm, GAn₂, GA113, GA|i₄,GA115, GA116, GAi i7, GAi is, GAn9, GAno, GAi₂i, GAi₂₂, GAi₂₃, GAi₂₄,GAi₂₅, and/or GAi26. The preferred gibberellin is the gibberellic acid,GA3.

The auxins, preferably indole-3-butyric acid (IBA), are present in thenon-aqueous solution in an amount such that the auxin is between about0.001 to 10 wt. %, preferably between about 0.005 to about 5 wt. %,preferably between 0.005 to about 2 wt. %, preferably between 0.005 toabout 1 wt. %, preferably between 0.005 to about 0.5 wt. %, preferablybetween 0.005 to about 0.85 wt. %, and preferably between about 0.005 toabout 0.05 wt. % of the non-aqueous solution.

The gibberellin, preferably gibberellic acid (GA3), are present in thenon-aqueous solution in an amount such that the gibberellin is betweenabout 0.001 to 20 wt. %, preferably between about 0.001 to 15 wt. %,preferably between about 0.001 to 7.5 wt. %, preferably between about0.005 to about 5 wt. %, preferably between about 0.005 to about 1 wt. %,preferably between about 0.005 to about 0.11 wt. %, preferably betweenabout 0.005 to about 0.07 wt. %, and preferably between about 0.005 toabout 0.05 wt. % of the non-aqueous solution.

The cytokinin, preferably kinetin, are present in the non-aqueoussolution in an amount such that the cytokinin is between about 0.003 to0.3 wt. %, preferably between 0.009 to 0.15 wt. %, preferably betweenabout 0.0015 to 0.15 wt. %, and most preferably between about 0.01 to0.05 wt. % of the non-aqueous solution.

As provided in International Publication WO 2012068473, the contents ofwhich are expressly incorporated herein by reference, in a preferredembodiment of the present invention, the plant growth regulator areincluded as a PGR mixture of two plant hormones—cytokinin andgibberellin. When used together, the ratio of the plant growthregulators, cytokinin and gibberellin, preferably ranges from 1:10 to1:300 and more preferably from 1:20 to 1:40. A ratio of approximately1:30 is most preferable. Nonetheless, to obtain the best results, theabsolute amount of the cytokinins and gibberellins must varyproportionally to the volume/weight of the treated plants and theirfruit.

Additionally, in a preferred embodiment of the present invention, theplant growth regulator may include a PGR mixture of the following twophytohormones: cytokinin and auxin. When used together, the ratio of theplant growth regulators, cytokinin and auxin, preferably ranges from1:10 to 1:300 and more preferably from 1:20 to 1:40. A ratio ofapproximately 1:30 is most preferable. Nonetheless, to obtain the bestresults, the absolute amount of the cytokinins and gibberellins mustvary proportionally to the volume/weight of the treated plants and theirfruit.

Additionally, in a preferred embodiment of the present invention, theplant growth regulator may include a PGR mixture of three planthormones—cytokinin, gibberellin, and auxin. In a preferred mixture, thecytokinin is kinetin, the gibberellin is GA3, and the auxin is IBA. Whenused together, the amount of kinetin is preferably 4-6 times, and morepreferably 2-3 times more than the amount of gibberellic acid and theamount of IBA is preferably 1-1.5 times more than the amount ofgibberellic acid. The non-aqueous solution may preferably include: a)0.2-0.005 wt. %, more preferably 0.10-0.009 wt. % kinetin; b) 0.1-0.003wt. %, more preferably 0.05-0.005 wt. % GA3; and c) 0.1-0.003 wt. %,more preferably 0.05-0.005 wt. % IBA.

Polar and Semi-polar Organic Solvent

A wide variety of polar and semi-polar organic solvents may be used,including the polar and semi-polar organic solvents ethanol, n-propanol,iso-propanol, ethyl lactate, 3-hydroxybutyrate (ethyl and propylesters), glycols, glycerols, polyethylene glycol, polypropylene glycol,propylene carbonate and combinations thereof. Most preferably, propyleneglycol is used as the organic solvent in the non-aqueous solution of thepresent invention. In one embodiment of the present invention, the polarand semi-polar organic solvent is a single or combination of“non-volatile, polar or semi-polar organic solvents”, herein defined toexclude those volatile organic compounds (VOCs) with a vapor pressureless than 0.1 mm Hg at 20° C.

Additional Ingredients Includes/Excluded

A preferred embodiment of the present invention includes the addition ofsurfactants, antifoams, and/or preservatives known to those of skill inthe art. The surfactant may include, but are not limited to, the groupconsisting of carboxylates, sulfonates, natural oils, alkylamides,arylamides, alkylphenols, arylphenols, ethoxylated alcohols,polyethylene, carboxylic esters, polyalkylglycol esters,anhydrosorbitols, glycol esters, carboxylic amides, monoalkanolamine,polethylene fatty acid amides, polysorbates, cyclodextrins, sugar based,silicone based, polyalkylated alcohols, and alkylaryl ethoxylates. In apreferred embodiment, the non-aqueous solution consists of only theplant growth regulator(s), optional mineral(s), surfactant, and thepolar and semi-polar organic solvent(s) and any impurities inherenttherein.

In an alternate preferred embodiment, the non-aqueous solution onlyincludes one solvent, that is, the polar and semi-polar organic solvent.As previously indicated this non-aqueous solution may include smallamounts of water, preferably less than 5 wt. %, more preferably lessthan 1 wt. %, and most preferably less than 0.5 wt. %. Most preferably,the non-aqueous solution only includes one solvent, that is, the polarand semi-polar organic solvent with no intentional addition of water. Aspreviously indicated, the non-aqueous solution may further include aminerals selected from the group consisting of the alkaline earthmetals, transition metals, boron and mixtures thereof. Such mineralspreferably are selected from the group consisting of calcium, magnesium,zinc, copper, manganese, boron, iron, cobalt, molybdenum and mixturesthereof. When included, the minerals may be present in the range fromabout 0.001 to about 10.0 wt. %, preferably from about 0.001 to about3.0 wt. %. The non-aqueous solution optionally, but preferably, includesone or more minerals that assist in the uptake of the plant growthregulator(s) by plant tissues and/or compliment the utilization of theplant hormones by the plant tissues. Preferred minerals include zinc,nitrogen, potassium, calcium and boron, with nitrogen, potassium,calcium and/or boron. In a preferred embodiment, the metals include, butare not limited to, metal chlorides, metal sulfates, sodium or potassiumsalts of, and chelated metals. Specific examples include, but are notlimited to metal chlorides, metal sulfates, EDTA chelated metals, andother suitable metal compounds.

The non-aqueous solution may be combined with a nitrogen-containingfertilizer, such as a liquid nitrogen fertilizer comprisingapproximately one-half urea and one-half ammonium nitrate. Such a liquidnitrogen fertilizer has a nitrogen content of about 28 to 32 percent.Preferably, the liquid nitrogen fertilizer is blended with thenon-aqueous solution containing the plant growth regulator(s) and otherminerals, if any, just prior to application, such that only a singlefield application of the solution/fertilizer is needed, thereby reducinglabor and equipment costs that would otherwise be required due to alater nitrogen-only field application.

Method of Making

The non-aqueous solution is generally produced by dissolving at leastone plant growth regulator in at least one polar and semi-polar organicsolvent and either mixing at room temperature or at a temperature up tothe boiling point of the polar and semi-polar organic solvent, morepreferably below 120° C. and most preferably below 100° C. It isbelieved that heating the hormones in the polar and/or semi-polarorganic solvent up to 120° C. will not significantly degrade the plantgrowth regulators.

Application to Plants

In a preferred embodiment, the non-aqueous solution is combined withwater prior to application to the plant (e.g. within a few hours ofapplication to the plant) to provide a water-diluted composition. Theamount of water added to the non-aqueous solution depends on therequired concentration of the active ingredients needed to regulateplant growth as known to those of skill in the art.

In a more preferred embodiment of the methods of the present invention,a water-diluted composition of the non-aqueous solution of the plantgrowth regulator is applied to the roots, foliage, flowers or fruits ofa plant after planting. While application to the roots or tubers priorto planting or by soil application after planting, may produce the bestresults in some circumstances, in others, application to the foliage maybe preferred. The specific crop and the desired result must be takeninto account when selecting an application method. The non-aqueoussolution and/or water-diluted composition including the non-aqueoussolution may be applied using conventional irrigation or sprayequipment.

The method preferably includes the application of the non-aqueoussolution of plant growth regulators, such as a cytokinin, to the foliageand/or flowers of plants at or about the time of the beginning of plantflowering (e.g., during meiosis and when pollen is about to enterdehiscence). The non-aqueous solution may be applied to the soil in anyappropriate fashion, such as, for example, in an opened furrow near theplant roots, which furrow may subsequently be closed. It may also beapplied with various forms of irrigation, such as overhead or drip tape,or furrow irrigation, among others. Application of agriculturalchemicals may be accomplished in any of several ways well known to thoseskilled in the art, including but not limited to, foliar applications,soil applications, irrigation applications, etc. In a preferred methodof the invention, the non-aqueous solution is readied and applied to theroots of growing plants, or via the soil in which the plants aregrowing, through drip irrigation. Other fertigation-type applicationmethods that may be employed include, but are not limited to,broadcasting (e.g. conventional irrigation) and other types of placementapplication (e.g. side dressing; microjets, etc.). Broadcast applicationis an acceptable method, if sufficient irrigation is permitted to washthe non-aqueous solution from the foliage and above-ground tissues ofthe plants and into the soil/roots.

The present invention includes seeds, seed pieces, dry fertilizer, talc,gypsum or tubers for producing plants having dispersed on the surfacethereof a phytohormone, e.g., an auxin or other PGR, in an amounteffective to alter plant architecture as explained above, but in anamount insufficient to negatively affect growth of the plant tissues.When applied as a non-aqueous solution, the non-aqueous solutioncontaining the plant growth regulator, e.g., an auxin or another PGR,may be sprayed on seeds or tubers using conventional spray equipment.Alternatively, the seeds, fertilizer, talc, gypsum or tubers may beimmersed in a non-aqueous solution of the plant growth regulator. Seeds,fertilizers, talc, gypsum or tubers may be treated prior to planting byspraying with or by immersion in such non-aqueous solutions.

The preferred method of applying PGRs may be along with aboron-containing solution. Boron will stabilize the auxin in planttissues to which such solutions are applied. The application of a metalor metalloid, preferably boron, together with the PGR extends theeffective life of the PGR, thus permitting longer times between repeatapplications. Additionally, boron has been reported to haveinsecticidal, fungicidal and bacteriocidal activities. Accordingly, itis believed that application of PGRs, together with boron, will improvethe effect of the PGR in suppressing insect and pathogen infestation inplants.

Preferably, but optionally, a low concentration of potassium is alsoapplied together with the plant growth regulator to enhance the effectsof the plant hormone. Potassium, if applied with the cytokinin, ispreferably applied at very low concentrations between about ¼ lb. toabout 2 lbs. per acre, more preferably between about ½ lb. to about 1-½lbs. per acre, and most preferably about 1 lb. per acre.

While the methods of the present invention may be used withsubstantially all plants, they are particularly useful when applied tocrop plants, e.g., dry beans, soy beans, onions, cucumbers, tomatoes,potatoes, corn, cotton, canola, wheat and the like.

In a first step of applying the non-aqueous solution to the plants, theplant hormone is readied for application to the plants to be treated.The plant hormone is preferably applied to the plants in a non-aqueoussolution. Therefore, readying the plant hormone may include one or moreof the following activities: diluting the non-aqueous solution of theplant hormone with sufficient amounts of solvent to create the desiredconcentration of plant hormone, adding low concentrations of mineralsand/or other fertilizers to the diluted solution to enhance the effectsof the applied plant hormone, loading the non-aqueous solution of theplant hormone (with or without minerals and/or fertilizers) into asprayer or tank for subsequent application to the plants to be treated,calibrating the sprayer or dosing applicator to meter the desired amountof the solution of the plant hormone to the plants to be treated andtransporting the solution of the plant hormone (with or without mineralsand/or fertilizers) the location of the plants to be treated.

As provided in International Publication No. WO 2005/021715, thecontents of which are expressly incorporated herein by reference, auxinlevel may be manipulated within a desired range by application of aplant growth regulator or phytohormone, e.g., cytokinin or gibberellicacid.

International Publication No. WO 2012135366 and US Publication No.US20120295788, the contents of which are expressly incorporated hereinby reference, teach exogenous application to the plant canopy (i.e.leaves and flowers) of the plant growth regulator/phytohormonecytokinin. Additionally, the application of low concentrations ofpotassium along with the cytokinin has been found to substantiallyincrease the effect of the cytokinin.

Examples

Tables 2-4 and 6-8 shows Stability Studies for kinetin, IBA, and GA3 inthe products identified in further detail below. The EPA Guidelines onStability that issued on Nov. 16, 2012 to the Office of PesticidePrograms (OPP) relating to “Accelerated Storage Stability and CorrosionCharacteristics Study Protocol” were followed. As provided in the EPAGuidelines, accelerated storage stability can be used to fulfill EPAdata requirements. OPP has determined that this study, conducted for 14days at an elevated temperature (54° C.), provides adequate data incertain circumstances to allow EPA to make a regulatory findingregarding the stability of the product and the effect of the formulationon the product packaging.

The products evaluated in the Accelerated Storage Stability Testinginclude the Active Ingredients is supplied in Tables 1 and 5 below.Table 5 lists the active ingredient in a non-aqueous solution ofpropylene glycol as the solvent, which contains less than 0.5 wt. %water, in accordance with the present invention. The stability datacompares the non-aqueous solution of the plant hormones in accordancewith the present invention (referred to in this Example as “Organic”).Specifically, the non-aqueous solutions were formulated with propyleneglycol as the solvent instead of water with less than 0.5% water in thesolution. Propylene glycol is an acceptable solvent since it isconsidered a low Volatile Organic Compound (VOC) in some areas. A lowVOC is defined in this invention as a compound with a vapor pressureless than 0.1 mm Hg at 20° C. The vapor pressure of propylene glycol is0.08 mm Hg at 20° C. As can be seen in the Tables, the plant hormonesretained their stability the best in the Organic, i.e. non-aqueoussolutions, formulated with propylene glycol as the solvent in accordancewith the present invention. Tables 2 and 6 show the stability of Kinetinin the various compositions at 0, 7 and 14 days. Tables 3 and 7 show thestability of IBA in the various compositions at 0, 7 and 14 days. Tables4 and 8 show the stability of GA3 in the various compositions at 0, 7,and 14 days.

TABLE 1 Kinetin IBA GA₃ EPA EPA EPA EPA EPA EPA Label Label Label LabelLabel Label Label (max) (min) Label (max) (min) Label (max) (min) #10.090% 0.099% 0.081% 0.050% 0.0550% 0.0450% 0.050% 0.0550% 0.0450% #20.009% 0.010% 0.008% 0.005% 0.0055% 0.0045% 0.005% 0.0055% 0.0045% #30.15%  0.165% 0.135% 0.85%  0.9350% 0.7650% #4 (Aq) 0.09%  0.045% 0.03% #5 (Aq) 0.09%  0.050% 0.05% 

The product's provided in Table 1 correspond to the following labelsindicated below:

#1 - Plant Growth Regulators 10X #2 - Plant Growth Regulators 1X #3 -Plant Growth Regulator #4 - Competitors (3 yr. old) #5 - Plant GrowthRegulator 1X (Aqueous)

TABLE 2 Kinetin Stability data 0 days 7 days 14 days #1 100.0% 98.0%96.9% #2 100.0% 109.1% 100.0% #3 100.0% 102.9% 100.7% #4 14.2% 17.2%16.2% #5 100.0% 83.2% 68.9%

TABLE 3 IBA Stability data 0 days 7 days 14 days #1 100.0% 91.7% 89.6%#2 100.0% 98.0% 98.0% #3 100.0% 98.7% 100.0% #4 73.1% 64.9% 61.6% #5100.0% 94.0% 89.4%

TABLE 4 GA3 Stability data 0 days 7 days 14 days #1 100.0% 92.3% 88.7%#2 100.0% 95.9% 95.9% #4 0.3% 1.3% 1.3% #5 100.0% 0.0% 0.0%

TABLE 5 Solvent (Polar/Semi- Kinetin IBA GA₃ Polar) Mineral #6 0.0950.047 0.11 Polyethylene Glycol 200 None #7 0.095 0.047 0.07 PolyethyleneGlycol 400 None #8 0.090 0.05 0.05 Isopropanol None #9 0.100 0 0 EthylLactate/Glycerol None #10 0 0 7.5 Propylene Glycol None #11 0 0 15Propylene Glycol None #12 0 0 20 Propylene Glycol None #13 0.085 0.040.065 Propylene Glycol 1.2% MnCl₂ #14 0.09 0.04 0.07 Propylene Glycol 5%BMZ #15 0.085 0.04 0.055 Propylene Glycol 2.5% BMZ *BMZ = StollerMixrite BMZ: 0.9% B, 0.5% Mo, 4.5% Mn, 10.0% Zn

TABLE 6 Kinetin Stability Data 0 days 7 days 14 days #6 100.0% 100.0%100.0% #7 100.0% 100.0% 100.0% #8 100.0% 100.0% 100.0% #9 100.0% 100.0%100.0% #13 100.0% 96.1% 87.6% #14 100.0% 100.2% 98.6% #15 100.0% 95.9%85.5%

TABLE 7 IBA Stability Data 0 days 7 days 14 days #6 100.0% 99.6% 96.6%#7 100.0% 98.5% 95.5% #8 100.0% 97.2% 95.0% #9 100.0% 103.6% 103.6% #13100.0% 51.0% 0.0% #14 100.0% 97.4% 93.0% #15 100.0% 63.2% 52.4%

TABLE 8 GA3 Stability Data 0 days 7 days 14 days #6 100.0% 100.2% 97.2%#7 100.0% 98.9% 99.3% #8 100.0% 100.5% 101.1% #9 100.0% 98.3% 91.7% #10100.0% 98.9% 101.3% #11 100.0% 100.0% 100.0% #12 100.0% 100.6% 99.9% #13100.0% 95.4% 95.5% #14 100.0% 92.9% 83.3% #15 100.0% 100.0% 90.9%

The present non-aqueous solution of plant growth regulators (PGRs), suchas auxins and gibberellins, in a polar or semi-polar organic solventhave been shown to have increased stability compared to aqueous-basedcompositions. The increased stability makes the non-aqueous solutionmore effective in improving the growth and productivity of plants byaltering plant architecture as explained above. Significantly, theseimprovements have been achieved without the use of environmentallyhazardous chemicals. The methods to the present invention achieve theseimprovements by applying naturally occurring or synthetic plant hormonesto adjust the phytohormone levels and ratios within the plant tissues toproduce the desired results.

Although the present invention has been disclosed in terms of apreferred embodiment, it will be understood that numerous additionalmodifications and variations could be made thereto without departingfrom the scope of the invention.

1. A solution comprising: a) from about 0.005 to about 0.05 wt. %indole-3-butyric acid; b) from 0.009 to 0.10 wt. % kinetin; c) from0.003 to 0.1 wt. % gibberellic acid (GA₃); and d) polyethylene glycol;wherein the solution comprises less than 1 wt. % water.
 2. The solutionof claim 1 which further comprises a polar organic solvent.
 3. Thesolution of claim 1 which further comprises a polar organic solvent withthe proviso that polar organic solvents defined as volatile organiccompounds by the United States Environmental Protection Agency areexcluded.
 4. The solution of claim 1 wherein the solution providesincreased stability compared to an aqueous based composition whereinstability is determined according to the EPA Guidelines on Stabilityissued on Nov. 16,
 2012. 5. The solution of claim 2 wherein the solutionprovides increased stability compared to an aqueous based compositionwherein stability is determined according to the EPA Guidelines onStability issued on Nov. 16,
 2012. 6. The solution of claim 3 whereinthe solution provides increased stability compared to an aqueous basedcomposition wherein stability is determined according to the EPAGuidelines on Stability issued on Nov. 16,
 2012. 7. The solution ofclaim 1 wherein the solution further comprises a surfactant.
 8. Thesolution of claim 1 wherein the solution comprises less than 0.5 wt. %water.
 9. The solution of claim 1 wherein said indole-3-butyric acid,said kinetin, and said gibberellic acid (GA₃) retain at least 90%activity after 14 days of Accelerated Storage Stability Testing.
 10. Anon-aqueous solution comprising: a) from about 0.005 to about 0.85 wt. %indole-3-butyric acid; b) from about 0.003 to about 0.3 wt. % kinetin;and c) polyethylene glycol; wherein the solution comprises less than 5wt. % water.
 11. The non-aqueous solution of claim 10 further comprisinga gibberellin.
 12. The non-aqueous solution of claim 11 furthercomprising gibberellic acid (GA₃).
 13. The non-aqueous solution of claim12 wherein the gibberellic acid (GA₃) comprises from 0.003 to 0.1 wt. %.14. The non-aqueous solution of claim 10 wherein the solution comprisesless than 1 wt. % water.
 15. The non-aqueous solution of claim 10further comprising a preservative or surfactant.
 16. The non-aqueoussolution of claim 10 further comprising an antifoam, a polar organicsolvent, or mixture thereof.
 17. The non-aqueous solution of claim 10further comprising a glycol.
 18. The non-aqueous solution of claim 10wherein the solution provides increased stability compared to an aqueousbased composition wherein stability is determined according to the EPAGuidelines on Stability issued on Nov. 16,
 2012. 19. The non-aqueoussolution of claim 10 wherein the solution comprises less than 0.5 wt. %water.
 20. The non-aqueous solution of claim 10 wherein saidindole-3-butyric acid and said kinetin retain at least 90% activityafter 14 days of Accelerated Storage Stability Testing.